Digestive System

Question 1

what cells line the GI tract

Answer 1

epithelium

Question 2

give an example of an accessory organ

Answer 2

tongue, salivary glands, pancreas, liver, gallbladder

Question 3

list the 7 activities of the digestive system

Answer 3

ingestion, mastication, deglutination, digestion, absorption, peristalsis, defecation

Question 4

what is chyme?

Answer 4

soupy substance produced as a result of mastication + chemical digestion

Question 5

describe the structure of the GI tract wall

Answer 5

serosa (epithelium), muscularis (smooth muscle) , submucosa (connective tissue with lymph nodules), mucosa (mucus + epithelium secretes enzymes)

Question 6

where does most of the chemical digestion take place

Answer 6

small intestine (enzymes)

Question 7

describe the structure of the muscle in the GI tract

Answer 7

smooth muscle which is circular and longitudinal

Question 8

why is pepsinogen in an inactive form

Answer 8

to prevent it from digesting the digestive system itself as it digests proteins

Question 9

what are the 4 regions of the stomach

Answer 9

cardia, fundus, body, pylorus

Question 10

what are the longitudinal folds in the mucosa layer called

Answer 10

gastric folds/rugae

Question 11

what do goblet cells secrete

Answer 11

protective mucous

Question 12

what do parietal cells secrete

Answer 12

hydrochloric acid

Question 13

what do chief cells secrete

Answer 13

pepsinogen

Question 14

what do argentaffin cells secrete

Answer 14

serotonin, histamine and autocrine regulators

Question 15

what do endocrine cells secrete (G cells)

Answer 15

secrete the hormone gastrin into the blood

Question 16

what hormone controls the production of gastric juice

Answer 16

gastrin

Question 17

What is the pH of the stomach?

Answer 17

pH 2

Question 18

What is the pancreas?

Answer 18

A long gland that lies beneath the stomach and is surrounded by the curve of the duodenum. It produces pancreatic juices that contains digestive enzymes and an alkaline solution that helps neutralise the acidic chyme

Question 19

How does the liver help with digestion?

Answer 19

It aids the digestion of lipids by secreting bile - bile salts (manufactured from cholesterol in the liver) emulsify lipids

Question 20

Where are nutrients absorbed?

Answer 20

Small intestine

Question 21

How do amino acids and monosaccharides pass into an epithelial cell of a villus in the intestines

Answer 21

By using a carrier molecule

Question 22

Role of large intestine

Answer 22

To absorb sodium ions and water, to eliminate wastes and to provide a home for friendly bacteria

Question 23

What vitamins do bacteria in the large intestine produce

Answer 23

Vitamin K

Question 24

What is dietary fibre important for in the colon?

Answer 24

regular movement of faeces